Key Technology Research For Micro Inertial Measurement System

In this dissertation, according to the requirements of the practical task for air-ammunition, mathematics model, test, drift modeling, signal de-nosing of micro-machined gyroscope, attitude updating and transfer alignment on moving base key technologies etc. were studied. And a new grope was performed in theory and in air-ammunition engineering application.1. The differential equation of vibrant micro-mechanical gyro was educed, and then the performance indexes were analyzed.A single velocity test method was presented according to the actual engineering demand, and the test result was similar with that of the multe-velocity test by comparison. It showed the method is feasible in check-and-acceptance test and late stability test.2. The error resources were analyzed and computed by Allan square error and GJB methods, and error coefficients gotten by two methods are almost the same. Pretreated drift data is modeled, and from the corner of easy realization in engineering, ARMA(2,1) is adopted by ARMA modeling.The drift is respectively 14.84 byte and 2.97 byte before and after compensation, and the precision of drift improved by 3.74 times3. Put forward two improved grey modeling methods based on temperature drift error analysis and temperature experiment data of some micro-mechanical gyro: on the one hand, the model is built after drift data preteatmen; On the other hand, numberical calculation of the differential equation is adopted considering from the GM(1,1) model mechanism. The precision of improved GM(1,1) model I is improved by 4.02 times compared with traditional GM(1,1).4. On the basis of actual measured data, a de-noising method for gyro signal is put forward based on local-wave decomposition method, and compared with wavlet threshold de-noising method.Carried on gyro signal de-noising by wavelet transformation and local-wave decomposition, the experiment showed they are ability in de-noising; In wavlet threshold method, exponential threshold function is adopted to avoid signal surging, sym6 wavelet selected and decomposition scale principle determined. In local-wave method, the intrinsic mode decomposition is adopted and noise relative discrimation, and this method is more derective and is not influnced by wavelet.5. According to the characteristics of the short-time navigation system for some air-ammunition and the required performance indexes, the micro inertial measurement system is designed. And then the attitude differential equation and attitude matrix based on modified rodrigues parameters method are educed.Under the input of angle velocity vector, the calculational precision of quaternion and modified rodrigues parameters algorithm is almost the same.The calculational quantity of modified rodrigues parameters algorithm is less 40% and 70% than that of quaternion and rotation vector.Pitch,roll and yaw angle commendably track the attitude of three-axle turntable by hardware-in-the-loop simulation,and it showed the method suit for attitude updating of air- ammunition.6.According to the advantages and disadvantagesof all kinds of transfer alignment methods and combined characteristics of aircraft,velocity+attitude matching method is adopted.The errors are etimated by fuzzy adaptive Kalman filter on the base of the reasonable simplification of transfer alignment mathematic model. Simulation and experiment of static, vehicle and flight showed the precision satisfied the request, and it can be applied in engineering pratice.Under the control request for the plane, a kind of available approximate precision test is presented for engineering application...